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    <td bgcolor="#666699" width="10"><b><a href="http://irrlicht.sourceforge.net" target="_blank"><img src="../../media/irrlichtlogo.jpg" width="88" height="31" border="0"></a></b></td>
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        <div align="left"><b><font color="#FFFFFF">Tutorial 11. Per pixel lighting</font></b></div>
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        <p> This tutorial shows how to use one of the built in more complex materials 
          in irrlicht: Per pixel lighted surfaces using normal maps and parallax 
          mapping. It will also show how to use fog and moving particle systems. 
          And don't panic: You dont need any experience with shaders to use these 
          materials in Irrlicht.</p>
        <p>The program which is described here will look like this:</p>
        <p align="center"><img src="../../media/011shot.jpg" width="258" height="202"><br>
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    <td bgcolor="#666699"> <b><font color="#FFFFFF">Lets start!</font></b></td>
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    <td height="90" bgcolor="#eeeeff" valign="top"> <div align="left"> 
        <div align="left"> 
          <p>At first, we need to include all headers and do the stuff we always 
            do, like in nearly all other tutorials.</p>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
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              <td> <pre>#include &lt;irrlicht.h&gt;<br>#include &lt;iostream&gt;<br><br>using namespace irr;<br><br>#pragma comment(lib, &quot;Irrlicht.lib&quot;)<br></pre></td>
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          <p>For this example, we need an event receiver, to make it possible 
            for the user to switch between the three available material types. 
            In addition, the event receiver will create some small GUI window 
            which displays what material is currently being used. There is nothing 
            special done in this class, so maybe you want to skip reading it.</p>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
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              <td><pre>class MyEventReceiver : public IEventReceiver
{
public:

	MyEventReceiver(scene::ISceneNode* room, 
		gui::IGUIEnvironment* env, video::IVideoDriver* driver)
	{
		// store pointer to room so we can change its drawing mode
		Room = room;
		Driver = driver;

		// set a nicer font
		gui::IGUISkin* skin = env->getSkin();
		gui::IGUIFont* font = env->getFont("../../media/fonthaettenschweiler.bmp");
		if (font)
			skin->setFont(font);

		// add window and listbox
		gui::IGUIWindow* window = env->addWindow(
			core::rect<s32>(490,390,630,470), false, L"Use 'E' + 'R' to change");

		ListBox = env->addListBox(
			core::rect<s32>(2,22,135,78), window);

		ListBox->addItem(L"Diffuse");
		ListBox->addItem(L"Bump mapping");
		ListBox->addItem(L"Parallax mapping");
		ListBox->setSelected(1);

		// create problem text
		ProblemText = env->addStaticText(
			L"Your hardware or this renderer is not able to use the "\
			L"needed shaders for this material. Using fall back materials.",
			core::rect<s32>(150,20,470,60));

		ProblemText->setOverrideColor(video::SColor(100,255,255,255));

		// set start material (prefer parallax mapping if available)
		video::IMaterialRenderer* renderer = 
			Driver->getMaterialRenderer(video::EMT_PARALLAX_MAP_SOLID);
		if (renderer && renderer->getRenderCapability() == 0)
			ListBox->setSelected(2);

		// set the material which is selected in the listbox
		setMaterial();
	}

	bool OnEvent(const SEvent& event)
	{
		// check if user presses the key 'E' or 'R'
		if (event.EventType == irr::EET_KEY_INPUT_EVENT &&
			!event.KeyInput.PressedDown && Room && ListBox)
		{
			// change selected item in listbox 

			int sel = ListBox->getSelected();
			if (event.KeyInput.Key == irr::KEY_KEY_R)
				++sel;
			else
			if (event.KeyInput.Key == irr::KEY_KEY_E)
				--sel;
			else 
				return false;

			if (sel > 2) sel = 0;
			if (sel < 0) sel = 2;
			ListBox->setSelected(sel);
			
			// set the material which is selected in the listbox
			setMaterial();
		}

		return false;
	}

private:

	// sets the material of the room mesh the the one set in the 
	// list box.
	void setMaterial()
	{
		video::E_MATERIAL_TYPE type = video::EMT_SOLID;

		// change material setting
		switch(ListBox->getSelected())
		{
		case 0: type = video::EMT_SOLID;
			break;
		case 1: type = video::EMT_NORMAL_MAP_SOLID;
			break;
		case 2: type = video::EMT_PARALLAX_MAP_SOLID;
			break;
		}

		Room->setMaterialType(type);</pre>
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          <p>We need to add a warning if the materials will not be able to be 
            displayed 100% correctly. This is no problem, they will be renderered 
            using fall back materials, but at least the user should know that 
            it would look better on better hardware. We simply check if the material 
            renderer is able to draw at full quality on the current hardware. 
            The IMaterialRenderer::getRenderCapability() returns 0 if this is 
            the case.<br>
          </p>
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              <td> <pre>video::IMaterialRenderer* renderer = Driver->getMaterialRenderer(type);

		// display some problem text when problem
		if (!renderer || renderer->getRenderCapability() != 0)
			ProblemText->setVisible(true);
		else
			ProblemText->setVisible(false);
	}

private:

	gui::IGUIStaticText* ProblemText;
	gui::IGUIListBox* ListBox;

	scene::ISceneNode* Room;	
	video::IVideoDriver* Driver;
};</pre></td>
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          <p><br>
            Now for the real fun. We create an Irrlicht Device and start to setup 
            the scene.<br>
          </p>
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              <td> <pre>int main()
{
	// let user select driver type

	video::E_DRIVER_TYPE driverType = video::EDT_DIRECT3D9;
<br>	printf(&quot;Please select the driver you want for this example:\n&quot;\<br>		&quot; (a) Direct3D 9.0c\n (b) Direct3D 8.1\n (c) OpenGL 1.5\n&quot;\<br>		&quot; (d) Software Renderer\n (e) Apfelbaum Software Renderer\n&quot;\<br>		&quot; (f) NullDevice\n (otherKey) exit\n\n&quot;);<br>
	char i;
	std::cin >> i;

	switch(i)<br>	{<br>		case 'a': driverType = video::EDT_DIRECT3D9;break;<br>		case 'b': driverType = video::EDT_DIRECT3D8;break;<br>		case 'c': driverType = video::EDT_OPENGL;   break;<br>		case 'd': driverType = video::EDT_SOFTWARE; break;<br>		case 'e': driverType = video::EDT_BURNINGSVIDEO;break;<br>		case 'f': driverType = video::EDT_NULL;     break;<br>		default: return 0;<br>	}	

	// create device

	IrrlichtDevice* device = createDevice(driverType, core::dimension2d<s32>(640, 480));

	if (device == 0)
		return 1; // could not create selected driver.
</pre></td>
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          <br>
          Before we start with the interesting stuff, we do some simple things: 
          Store pointers to the most important parts of the engine (video driver,<br>
          scene manager, gui environment) to safe us from typing too much, add 
          an irrlicht engine logo to the window and a user controlled first person 
          shooter style camera. Also, we let the engine now that it should store 
          all textures in 32 bit. This necessary because for parallax mapping, 
          we need 32 bit textures.<br>
          <br>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
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              <td> <pre>
	video::IVideoDriver* driver = device->getVideoDriver();
	scene::ISceneManager* smgr = device->getSceneManager();
	gui::IGUIEnvironment* env = device->getGUIEnvironment();

	driver->setTextureCreationFlag(video::ETCF_ALWAYS_32_BIT, true);

	// add irrlicht logo
	env->addImage(driver->getTexture("../../media/irrlichtlogoalpha.tga"),
		core::position2d<s32>(10,10));
		
	// add camera
	scene::ICameraSceneNode* camera = 
		smgr->addCameraSceneNodeFPS(0,100.0f,300.0f);
	camera->setPosition(core::vector3df(-200,200,-200));

	// disable mouse cursor
	device->getCursorControl()->setVisible(false);</pre></td>
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          <br>
          Because we want the whole scene to look a little bit scarier, we add 
          some fog to it. This is done by a call to IVideoDriver::setFog(). There 
          you can set<br>
          various fog settings. In this example, we use pixel fog, because it 
          will work well with the materials we'll use in this example. Please 
          note that you will have to set the material flag EMF_FOG_ENABLE to 'true' 
          in every scene node which should be affected by this fog.<br>
          <br>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
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              <td> <pre>driver-&gt;setFog(video::SColor(0,138,125,81), true, 250, 1000, 0, true);<br></pre></td>
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          <br>
          To be able to display something interesting, we load a mesh from a .3ds 
          file which is a room I modeled with anim8or. It is the same room as 
          <br>
          from the specialFX example. Maybe you remember from that tutorial, I 
          am no good modeler at all and so I totally messed up the texture mapping 
          in this model, but we can simply repair it with the IMeshManipulator::makePlanarTextureMapping() 
          method.<br>
          <br>
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              <td> <pre>	scene::IAnimatedMesh* roomMesh = smgr->getMesh(
		"../../media/room.3ds");
	scene::ISceneNode* room = 0;

	if (roomMesh)
	{
		smgr->getMeshManipulator()->makePlanarTextureMapping(
				roomMesh->getMesh(0), 0.003f);</pre></td>
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          <br>
          Now for the first exciting thing: If we successfully loaded the mesh 
          we need to apply textures to it. Because we want this room to be displayed 
          with a very cool material, we have to do a little bit more than just 
          set the textures. Instead of only loading a color map as usual, we also 
          load a height map which is simply a grayscale texture. From this height 
          map, we create a normal map which we will set as second texture of the 
          room. If you already have a normal map, you could directly set it, but 
          I simply didn&acute;t find a nice normal map for this texture. The normal 
          map texture is being generated by the makeNormalMapTexture method<br>
          of the VideoDriver. The second parameter specifies the height of the 
          heightmap. If you set it to a bigger value, the map will look more rocky.<br>
          <br>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
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              <td> <pre>		video::ITexture* colorMap = driver->getTexture("../../media/rockwall.bmp");
		video::ITexture* normalMap = driver->getTexture("../../media/rockwall_height.bmp");
		
		driver->makeNormalMapTexture(normalMap, 9.0f);</pre></td>
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          <br>
          But just setting color and normal map is not everything. The material 
          we want to use needs some additional informations per vertex like tangents 
          and binormals.<br>
          Because we are too lazy to calculate that information now, we let Irrlicht 
          do this for us. That's why we call IMeshManipulator::createMeshWithTangents(). 
          It<br>
          creates a mesh copy with tangents and binormals from any other mesh. 
          After we've done that, we simply create a standard mesh scene node with 
          this<br>
          mesh copy, set color and normal map and adjust some other material settings. 
          Note that we set EMF_FOG_ENABLE to true to enable fog in the room.<br>
          <br>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
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              <td> <pre>scene::IMesh* tangentMesh = smgr-&gt;getMeshManipulator()-&gt;createMeshWithTangents(<br>			roomMesh-&gt;getMesh(0));<br>			<br>		room = smgr-&gt;addMeshSceneNode(tangentMesh);<br>		room-&gt;setMaterialTexture(0,	colorMap);<br>		room-&gt;setMaterialTexture(1,	normalMap);<br>		room-&gt;getMaterial(0).SpecularColor.set(0,0,0,0);<br>		room-&gt;setMaterialFlag(video::EMF_FOG_ENABLE, true);<br>		room-&gt;setMaterialType(video::EMT_PARALLAX_MAP_SOLID); <br>		room-&gt;getMaterial(0).MaterialTypeParam = 0.02f; // adjust height for parallax effect<br>		// drop mesh because we created it with a create.. call.<br>		tangentMesh-&gt;drop();<br>	}<br></pre></td>
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          <br>
          After we've created a room shaded by per pixel lighting, we add a sphere 
          into it with the same material, but we'll make it transparent. In addition,<br>
          because the sphere looks somehow like a familiar planet, we make it 
          rotate. The procedure is similar as before. The difference is that we 
          are loading <br>
          the mesh from an .x file which already contains a color map so we do 
          not need to load it manually. But the sphere is a little bit too small 
          for our needs, so we scale it by the factor 50.<br>
          <br>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
            <tr> 
              <td> <pre>// add earth sphere

	scene::IAnimatedMesh* earthMesh = smgr->getMesh("../../media/earth.x");
	if (earthMesh)
	{
		// create mesh copy with tangent informations from original earth.x mesh
		scene::IMesh* tangentSphereMesh = 
			smgr->getMeshManipulator()->createMeshWithTangents(earthMesh->getMesh(0));

		// set the alpha value of all vertices to 200
		smgr->getMeshManipulator()->setVertexColorAlpha(tangentSphereMesh, 200);
		
		// scale the mesh by factor 50
		smgr->getMeshManipulator()->scaleMesh(
			tangentSphereMesh, core::vector3df(50,50,50));

		// create mesh scene node
		scene::ISceneNode* sphere = smgr->addMeshSceneNode(tangentSphereMesh);
		sphere->setPosition(core::vector3df(-70,130,45));

		// load heightmap, create normal map from it and set it
		video::ITexture* earthNormalMap = driver->getTexture("../../media/earthbump.bmp");
		driver->makeNormalMapTexture(earthNormalMap, 20.0f);
		sphere->setMaterialTexture(1, earthNormalMap);

		// adjust material settings
		sphere->setMaterialFlag(video::EMF_FOG_ENABLE, true);
		sphere->setMaterialType(video::EMT_NORMAL_MAP_TRANSPARENT_VERTEX_ALPHA); 

		// add rotation animator
		scene::ISceneNodeAnimator* anim =
			smgr->createRotationAnimator(core::vector3df(0,0.1f,0));	
		sphere->addAnimator(anim);
		anim->drop();

		// drop mesh because we created it with a create.. call.
		tangentSphereMesh->drop();
	}</pre></td>
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          </table>
          <br>
          Per pixel lighted materials only look cool when there are moving lights. 
          So we add some. And because moving lights alone are so boring, we add 
          billboards <br>
          to them, and a whole particle system to one of them. We start with the 
          first light which is red and has only the billboard attached.<br>
          <br>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
            <tr> 
              <td> <pre>// add light 1 (nearly red)
	scene::ILightSceneNode* light1 = 
		smgr->addLightSceneNode(0, core::vector3df(0,0,0), 
		video::SColorf(0.5f, 1.0f, 0.5f, 0.0f), 200.0f);

	// add fly circle animator to light 1
	scene::ISceneNodeAnimator* anim = 
		smgr->createFlyCircleAnimator (core::vector3df(50,300,0),190.0f, -0.003f);
	light1->addAnimator(anim);
	anim->drop();

	// attach billboard to the light
	scene::ISceneNode* bill = 
		smgr->addBillboardSceneNode(light1, core::dimension2d<f32>(60, 60));

	bill->setMaterialFlag(video::EMF_LIGHTING, false);
	bill->setMaterialType(video::EMT_TRANSPARENT_ADD_COLOR);
	bill->setMaterialTexture(0, driver->getTexture("../../media/particlered.bmp"));</pre></td>
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          <br>
          Now the same again, with the second light. The difference is that we 
          add a particle system to it too. And because the light moves, the particles 
          of the particlesystem will follow. If you want to know more about how 
          particle systems are created in Irrlicht, take a look at the specialFx 
          example.<br>
          Maybe you will have noticed that we only add 2 lights, this has a simple 
          reason: The low end version of this material was written in ps1.1 and 
          vs1.1, which doesn't allow more lights. You could add a third light 
          to the scene, but it won't be used to shade the walls. But of course, 
          this will change in future versions of Irrlicht were higher versions 
          of pixel/vertex shaders will be implemented too.<br>
          <br>
          <table width="95%" border="0" cellspacing="2" cellpadding="0" bgcolor="#CCCCCC" align="center">
            <tr> 
              <td> <pre>// add light 2 (gray)
	scene::ISceneNode* light2 = 
		smgr->addLightSceneNode(0, core::vector3df(0,0,0), 
		video::SColorf(1.0f, 0.2f, 0.2f, 0.0f), 200.0f);

	// add fly circle animator to light 2
	anim = smgr->createFlyCircleAnimator (core::vector3df(0,150,0),200.0f); 
	light2->addAnimator(anim);
	anim->drop();

	// attach billboard to light
	bill = smgr->addBillboardSceneNode(light2, core::dimension2d<f32>(120, 120));
	bill->setMaterialFlag(video::EMF_LIGHTING, false);
	bill->setMaterialType(video::EMT_TRANSPARENT_ADD_COLOR);
	bill->setMaterialTexture(0, driver->getTexture("../../media/particlewhite.bmp"));

	// add particle system
	scene::IParticleSystemSceneNode* ps = 
		smgr->addParticleSystemSceneNode(false, light2);

	ps->setParticleSize(core::dimension2d<f32>(30.0f, 40.0f));

	// create and set emitter
	scene::IParticleEmitter* em = ps->createBoxEmitter(
		core::aabbox3d<f32>(-3,0,-3,3,1,3), 
		core::vector3df(0.0f,0.03f,0.0f),
		80,100, 
		video::SColor(0,255,255,255), video::SColor(0,255,255,255),
		400,1100);
	ps->setEmitter(em);
	em->drop();

	// create and set affector
	scene::IParticleAffector* paf = ps->createFadeOutParticleAffector();
	ps->addAffector(paf);
	paf->drop();

	// adjust some material settings
	ps->setMaterialFlag(video::EMF_LIGHTING, false);
	ps->setMaterialTexture(0, driver->getTexture("../../media/fireball.bmp"));
	ps->setMaterialType(video::EMT_TRANSPARENT_VERTEX_ALPHA);


	MyEventReceiver receiver(room, env, driver);
	device->setEventReceiver(&receiver);</pre></td>
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          <br>
          Finally, draw everything. That's it.<br>
          <br>
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              <td> <pre>int lastFPS = -1;

	while(device->run())
	if (device->isWindowActive())
	{
		driver->beginScene(true, true, 0);

		smgr->drawAll();
		env->drawAll();

		driver->endScene();

		int fps = driver->getFPS();

		if (lastFPS != fps)
		{
		  core::stringw str = L"Per pixel lighting example - Irrlicht Engine [";
		  str += driver->getName();
		  str += "] FPS:";
		  str += fps;

		  device->setWindowCaption(str.c_str());
		  lastFPS = fps;
		}
	}

	device->drop();
	
	return 0;
}
</pre></td>
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